@import url("https://fonts.googleapis.com/css2?family=Cormorant+Garamond:wght@400;500;600&family=Noto+Sans+SC:wght@300;400;500&family=Noto+Serif+SC:wght@400;500;600&display=swap");

/* ==================================================
   1. 全站主题变量
   以后调整颜色，只修改这一段。
================================================== */
:root {
    /* 基础颜色 */
    --color-background: #f7f4ef;
    --color-paper: #fffdf9;
    --color-text: #515b5b;
    --color-text-muted: #7c8583;
    --color-white: #ffffff;
    --color-gold: #9a7b45;

    /* 首页渐变 */
    --color-home-start: #f5dfd2;
    --color-home-middle: #eadcda;
    --color-home-end: #ccd8d2;
    --color-home-glow: rgba(255, 246, 222, 0.95);
    --color-home-sage-glow: rgba(174, 187, 173, 0.45);

    /* 两位角色的主题色 */
    --color-xia: #c6a58e;
    --color-xia-hover: #b59179;
    --color-xia-glow: rgba(216, 184, 160, 0.22);
    --color-qiyu: #91aab3;
    --color-qiyu-hover: #7897a1;
    --color-qiyu-glow: rgba(168, 187, 195, 0.25);

    /* 邀请函背景 */
    --color-invitation-xia-glow: rgba(216, 184, 160, 0.30);
    --color-invitation-qiyu-glow: rgba(168, 187, 195, 0.35);
    --color-card: rgba(255, 253, 249, 0.88);
    --color-border: rgba(91, 101, 98, 0.14);

    /* 弹窗 */
    --color-popup-overlay: rgba(63, 75, 76, 0.88);
    --color-popup-card: rgba(255, 253, 249, 0.08);
    --color-popup-border: rgba(255, 255, 255, 0.32);
    --color-popup-text: rgba(255, 255, 255, 0.82);
    --color-popup-decoration: #f2dfc8;

    /* 阴影 */
    --shadow-button: 0 10px 30px rgba(92, 113, 105, 0.18);
    --shadow-card: 0 20px 55px rgba(90, 99, 96, 0.12);
    --shadow-popup: 0 20px 65px rgba(41, 50, 51, 0.25);

    /* 尺寸 */
    --page-width: 1180px;
    --card-radius: 26px;
}


/* ==================================================
   2. 全站基础设置
================================================== */
* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    overflow-x: hidden;
    color: var(--color-text);
    background: var(--color-background);
    font-family: "Noto Sans SC", sans-serif;
    text-align: center;
}

h1,
h2,
h3,
.character-name,
.subtitle {
    font-family: "Cormorant Garamond", "Noto Serif SC", serif;
}

button {
    padding: 14px 30px;
    border: 0;
    border-radius: 30px;
    color: var(--color-white);
    background: var(--color-xia);
    font-family: Arial, "PingFang SC", sans-serif;
    font-size: 16px;
    cursor: pointer;
    transition: transform 0.3s ease, background-color 0.3s ease,
        box-shadow 0.3s ease;
}

button:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-button);
}

.page-hidden {
    display: none !important;
}


/* ==================================================
   3. 第一屏：生日首页
================================================== */
.welcome {
    width: 100%;
    min-height: 100vh;
    padding: 50px 25px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: var(--color-text);
    background:
        radial-gradient(circle at 20% 20%, var(--color-home-glow), transparent 42%),
        radial-gradient(circle at 85% 75%, var(--color-home-sage-glow), transparent 45%),
        linear-gradient(135deg, var(--color-home-start), var(--color-home-middle) 45%, var(--color-home-end));
}

.subtitle {
    margin: 0;
    color: var(--color-gold);
    font-size: 22px;
    font-weight: 500;
    letter-spacing: 4px;
}

h1 {
    margin: 20px 0;
    color: var(--color-text);
    font-size: clamp(60px, 11vw, 105px);
    font-weight: 500;
    letter-spacing: 4px;
    text-shadow: 0 5px 25px rgba(90, 99, 96, 0.13);
}

.message {
    margin: 0 0 35px;
    color: var(--color-text-muted);
    font-size: 25px;
    font-weight: 300;
    line-height: 1.8;
    letter-spacing: 2px;
}

#startButton {
    background: var(--color-qiyu-hover);
    box-shadow: var(--shadow-button);
}

#startButton:hover {
    background: var(--color-text);
}


/* ==================================================
   4. 第二屏：邀请函页面
================================================== */
.invitation-section {
    min-height: 100vh;
    padding: 80px 24px;
    color: var(--color-text);
    background:
        radial-gradient(circle at 10% 25%, var(--color-invitation-xia-glow), transparent 38%),
        radial-gradient(circle at 90% 70%, var(--color-invitation-qiyu-glow), transparent 40%),
        var(--color-background);
}

.invitation-heading {
    max-width: 800px;
    margin: 0 auto 50px;
}

.chapter-number {
    margin: 0 0 16px;
    color: var(--color-gold);
    font-family: Arial, sans-serif;
    font-size: 12px;
    letter-spacing: 5px;
}

.invitation-heading h2 {
    margin: 15px 0;
    color: var(--color-text);
    font-size: clamp(42px, 7vw, 70px);
    font-weight: 500;
    letter-spacing: 3px;
}

.invitation-tip {
    margin: 0;
    color: var(--color-text-muted);
    font-size: 21px;
    font-weight: 300;
    letter-spacing: 2px;
}

.invitation-list {
    width: 100%;
    max-width: var(--page-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 32px;
    align-items: stretch;
}

.invitation-card {
    position: relative;
    overflow: hidden;
    background: var(--color-card);
    border: 1px solid var(--color-border);
    border-radius: var(--card-radius);
    box-shadow: var(--shadow-card);
    transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.invitation-card:hover {
    transform: translateY(-8px);
}

.xia-card:hover {
    box-shadow: var(--shadow-card), 0 0 30px var(--color-xia-glow);
}

.qiyu-card:hover {
    box-shadow: var(--shadow-card), 0 0 30px var(--color-qiyu-glow);
}

.invitation-image {
    position: relative;
    overflow: hidden;
    aspect-ratio: 4 / 3;
}

.invitation-image::after {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(to bottom, transparent 42%, rgba(53, 65, 63, 0.70));
}

.invitation-image img {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: cover;
    transform: scale(1.02);
    transition: transform 0.8s ease;
}

.invitation-card:hover .invitation-image img {
    transform: scale(1.07);
}

.character-name {
    position: absolute;
    left: 28px;
    bottom: 22px;
    z-index: 2;
    color: var(--color-white);
    text-align: left;
}

.character-name span {
    display: block;
    font-size: 38px;
    letter-spacing: 4px;
}

.character-name small {
    display: block;
    margin-top: 5px;
    color: rgba(255, 255, 255, 0.75);
    font-family: Arial, sans-serif;
    font-size: 10px;
    letter-spacing: 4px;
}

.invitation-content {
    padding: 32px 32px 38px;
}

.invitation-symbol {
    margin: 0 0 10px;
    font-size: 22px;
    letter-spacing: 8px;
}

.xia-card .invitation-symbol {
    color: var(--color-xia);
}

.qiyu-card .invitation-symbol {
    color: var(--color-qiyu);
}

.invitation-content h3 {
    margin: 0 0 20px;
    color: var(--color-text);
    font-size: 30px;
    font-weight: 500;
    letter-spacing: 2px;
}

.invitation-letter {
    min-height: 115px;
    margin: 0 0 28px;
    color: var(--color-text-muted);
    font-size: 20px;
    font-weight: 300;
    line-height: 1.8;
}

.invitation-button {
    width: 100%;
}

.xia-card .invitation-button {
    background: var(--color-xia);
}

.xia-card .invitation-button:hover {
    background: var(--color-xia-hover);
}

.qiyu-card .invitation-button {
    background: var(--color-qiyu);
}

.qiyu-card .invitation-button:hover {
    background: var(--color-qiyu-hover);
}


/* ==================================================
   5. 烟花弹窗
================================================== */
.birthday-popup {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: none;
    align-items: center;
    justify-content: center;
    overflow: hidden;
    background: var(--color-popup-overlay);
}

.birthday-popup.show {
    display: flex;
}

.popup-card {
    position: relative;
    z-index: 2;
    width: 90%;
    max-width: 520px;
    padding: 50px 30px;
    background: var(--color-popup-card);
    border-radius: 28px;
    box-shadow: var(--shadow-popup);
    backdrop-filter: blur(15px);
    -webkit-backdrop-filter: blur(15px);
    animation: popupAppear 0.8s ease;
}

.popup-decoration {
    margin: 0 0 15px;
    color: var(--color-popup-decoration);
    font-size: 26px;
    letter-spacing: 8px;
}

.popup-card h2 {
    margin: 0 0 20px;
    color: var(--color-white);
    font-family: "Cormorant Garamond", "Noto Serif SC", serif;
    font-size: clamp(36px, 7vw, 58px);
    font-weight: 400;
}

.popup-message {
    margin: 0 0 30px;
    color: var(--color-popup-text);
    font-size: 22px;
    line-height: 1.8;
}

#closeButton {
    color: var(--color-text);
    background: var(--color-popup-decoration);
}

#closeButton:hover {
    background: var(--color-white);
}

@keyframes popupAppear {
    from {
        opacity: 0;
        transform: scale(0.8) translateY(30px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}


/* ==================================================
   6. 烟花粒子
================================================== */
.fireworks {
    position: absolute;
    inset: 0;
    z-index: 1;
    pointer-events: none;
}

.firework {
    position: absolute;
    width: 5px;
    height: 5px;
}

.spark {
    position: absolute;
    width: 9px;
    height: 9px;
    border-radius: 50%;
    opacity: 0.95;
    background: var(--spark-color);
    box-shadow:
        0 0 6px var(--spark-color),
        0 0 15px 3px var(--spark-color),
        0 0 28px 5px rgba(255, 255, 255, 0.24);
    animation: explode 2.6s ease-out forwards;
}

@keyframes explode {
    0% {
        opacity: 0.8;
        transform: translate(0, 0) scale(0.3);
    }
    18% {
        opacity: 0.88;
    }
    70% {
        opacity: 0.55;
    }
    100% {
        opacity: 0;
        transform: translate(var(--move-x), var(--move-y)) scale(0.2);
    }
}


/* ==================================================
   7. iPhone 竖屏：上下两张横向邀请函
================================================== */
@media (max-width: 700px) and (orientation: portrait) {
    .invitation-section {
        padding: 55px 14px 45px;
    }
    .invitation-heading {
        margin-bottom: 30px;
    }
    .invitation-heading h2 {
        font-size: 36px;
    }
    .invitation-tip {
        font-size: 16px;
    }
    .invitation-list {
        max-width: 470px;
        grid-template-columns: 1fr;
        gap: 22px;
    }
    .invitation-card {
        min-height: 255px;
        display: grid;
        grid-template-columns: 38% minmax(0, 1fr);
    }
    .invitation-image {
        height: 100%;
        aspect-ratio: auto;
    }
    .character-name {
        left: 14px;
        bottom: 14px;
    }
    .character-name span {
        font-size: 27px;
        letter-spacing: 2px;
    }
    .character-name small {
        font-size: 7px;
        letter-spacing: 2px;
    }
    .invitation-content {
        padding: 22px 18px;
        display: flex;
        flex-direction: column;
        justify-content: center;
    }
    .invitation-symbol {
        font-size: 16px;
        letter-spacing: 4px;
    }
    .invitation-content h3 {
        margin-bottom: 10px;
        font-size: 21px;
    }
    .invitation-letter {
        min-height: 0;
        margin-bottom: 15px;
        font-size: 13px;
        line-height: 1.6;
    }
    .invitation-button {
        padding: 10px 12px;
        font-size: 12px;
    }
    .message {
        font-size: 21px;
    }
    .popup-card {
        padding: 42px 22px;
    }
}


/* ==================================================
   8. iPhone 横屏：两张邀请函并排，每张图片在上、文字在下
================================================== */
@media (orientation: landscape) and (max-height: 600px) {
    .invitation-section {
        padding: 42px 16px 35px;
    }
    /* 缩小页面标题区域 */
    .invitation-heading {
        margin-bottom: 28px;
    }
    .invitation-heading h2 {
        font-size: 38px;
    }
    .invitation-tip {
        font-size: 15px;
    }
    /* 两张邀请函左右并排 */
    .invitation-list {
        width: 100%;
        max-width: 950px;
        display: grid;
        grid-template-columns: repeat(2, minmax(0, 1fr));
        gap: 20px;
        align-items: start;
    }
    /* 取消竖屏时的左右布局，强制每张邀请函从上到下排列。*/
    .invitation-card {
        width: 100%;
        min-height: 0;
        display: flex !important;
        flex-direction: column !important;
    }
    /* 图片强制放在卡片上方 */
    .invitation-image {
        width: 100% !important;
        height: auto !important;
        aspect-ratio: 3 / 4 !important;
        flex: none;
    }
    /* 图片填满上方区域 */
    .invitation-image img {
        width: 100%;
        height: 100%;
        object-fit: cover;
        object-position: center top;
    }
    /* 文字区域放在图片下方 */
    .invitation-content {
        width: 100%;
        padding: 22px 18px 26px;
        display: flex;
        flex-direction: column;
        flex: 1;
    }
    .invitation-symbol {
        font-size: 16px;
        letter-spacing: 4px;
    }
    .invitation-content h3 {
        margin-bottom: 10px;
        font-size: 23px;
    }
    .invitation-letter {
        min-height: 88px;
        margin-bottom: 16px;
        font-size: 14px;
        line-height: 1.55;
    }
    /* 按钮对齐到卡片底部 */
    .invitation-button {
        margin-top: auto;
        padding: 10px 14px;
        font-size: 12px;
    }
}


/* ==================================================
   9. 沉浸式信件弹窗
================================================== */

/* 弹窗背景：默认隐藏 */
.letter-modal {
    position: fixed;
    inset: 0;
    z-index: 3000;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 24px;
    background: rgba(58, 61, 60, 0.48);
    backdrop-filter: blur(8px);
    -webkit-backdrop-filter: blur(8px);
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transition:
        opacity 0.45s ease,
        visibility 0.45s ease;
}
/* 打开弹窗后的状态 */
.letter-modal.is-open {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
}
/* 信纸 */
.letter-paper {
    position: relative;
    width: min(680px, 100%);
    min-height: 520px;
    max-height: 86vh;
    overflow-y: auto;
    padding: 58px 62px 42px;
    color: var(--color-text);
    background:
        linear-gradient(
            rgba(255, 253, 249, 0.96),
            rgba(250, 246, 238, 0.98)
        );
    border: 1px solid rgba(154, 123, 69, 0.18);
    border-radius: 6px;
    box-shadow:
        0 25px 70px rgba(45, 49, 47, 0.24),
        inset 0 0 40px rgba(198, 165, 142, 0.08);
    /* 打开前稍微向下 */
    transform: translateY(25px) scale(0.97);
    transition: transform 0.5s ease;
    cursor: pointer;
}
/* 弹窗打开时，信纸向上出现 */
.letter-modal.is-open .letter-paper {
    transform: translateY(0) scale(1);
}
/* 信纸上的淡淡横线 */
.letter-paper::before {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    background: repeating-linear-gradient(
        to bottom,
        transparent 0,
        transparent 35px,
        rgba(145, 170, 179, 0.08) 36px
    );
}
/* 信件中的内容放在横线上方 */
.letter-paper > * {
    position: relative;
    z-index: 1;
}
/* 右上角关闭按钮 */
.letter-close-button {
    position: absolute;
    top: 18px;
    right: 22px;
    width: 38px;
    height: 38px;
    padding: 0;
    border: 0;
    border-radius: 50%;
    color: var(--color-text-muted);
    background: rgba(255, 255, 255, 0.6);
    font-family: Arial, sans-serif;
    font-size: 26px;
    line-height: 38px;
    cursor: pointer;
    transition:
        color 0.25s ease,
        background 0.25s ease,
        transform 0.25s ease;
}
.letter-close-button:hover {
    color: var(--color-text);
    background: rgba(255, 255, 255, 0.95);
    transform: rotate(6deg);
}
/* 上方英文小标题 */
.letter-small-title {
    margin: 0 0 12px;
    color: var(--color-gold);
    font-size: 13px;
    letter-spacing: 0.2em;
    text-align: center;
}
/* 信件标题 */
.letter-title {
    margin: 0 0 36px;
    font-size: 34px;
    font-weight: 500;
    text-align: center;
}
/* 所有信件段落的容器 */
.letter-text {
    min-height: 270px;
}
/* 每一段文字 */
.letter-paragraph {
    margin: 0 0 24px;
    font-size: 18px;
    line-height: 2;
    letter-spacing: 0.05em;
    text-align: justify;
    opacity: 0;
    transform: translateY(15px);
    filter: blur(4px);
    transition:
        opacity 1.1s ease,
        transform 1.1s ease,
        filter 1.1s ease;
}
/* 当前需要显示的段落 */
.letter-paragraph.is-visible {
    opacity: 1;
    transform: translateY(0);
    filter: blur(0);
}
/* 底部阅读提示 */
.letter-reading-tip {
    margin: 26px 0 0;
    color: var(--color-text-muted);
    font-size: 13px;
    letter-spacing: 0.08em;
    text-align: center;
    animation: readingTip 1.8s ease-in-out infinite;
}
/* 提示文字轻轻呼吸 */
@keyframes readingTip {
    0%,
    100% {
        opacity: 0.45;
    }
    50% {
        opacity: 1;
    }
}

/* ==================================================
   手机竖屏状态下的信件尺寸
================================================== */
@media (max-width: 600px) {
    .letter-modal {
        padding: 15px;
    }
    .letter-paper {
        min-height: 72vh;
        max-height: 88vh;
        padding: 54px 28px 32px;
    }
    .letter-title {
        margin-bottom: 28px;
        font-size: 28px;
    }
    .letter-paragraph {
        font-size: 16px;
        line-height: 1.9;
    }
    .letter-text {
        min-height: 300px;
    }
}

/* ==================================================
   手机横屏状态下的信件尺寸
================================================== */
@media (orientation: landscape) and (max-height: 600px) {
    .letter-modal {
        padding: 12px;
    }
    .letter-paper {
        width: min(760px, 92%);
        min-height: 0;
        max-height: 92vh;
        padding: 42px 48px 26px;
    }
    .letter-title {
        margin-bottom: 20px;
        font-size: 27px;
    }
    .letter-text {
        min-height: 130px;
    }
    .letter-paragraph {
        margin-bottom: 16px;
        font-size: 15px;
        line-height: 1.75;
    }
    .letter-reading-tip {
        margin-top: 14px;
    }
}


/* ========================================
   邀请函显示控制
======================================== */
/* 刚进入网站时，邀请函完全隐藏 */
.invitation-section {
    display: none;
}
/* JavaScript 添加 is-visible 后，邀请函才会显示。*/
.invitation-section.is-visible {
    display: block;
}

/* ========================================
   进入网站前的验证页面
======================================== */

/* 尚未验证时禁止页面滚动，防止用户向下看到生日首页。
*/
body.site-locked {
    height: 100vh;
    overflow: hidden;
}

/* 验证页面覆盖整个屏幕 */
.access-gate {
    position: fixed;
    inset: 0;
    z-index: 5000;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 25px;
    background:
        radial-gradient(
            circle at 20% 20%,
            var(--color-home-glow),
            transparent 40%
        ),
        radial-gradient(
            circle at 85% 75%,
            var(--color-home-sage-glow),
            transparent 43%
        ),
        linear-gradient(
            135deg,
            var(--color-home-start),
            var(--color-home-middle) 48%,
            var(--color-home-end)
        );
}

/* 验证卡片 */
.access-card {
    width: 100%;
    max-width: 460px;
    padding: 48px 35px;
    border: 1px solid var(--color-border);
    border-radius: 28px;
    background: rgba(255, 253, 249, 0.72);
    box-shadow:
        0 25px 70px rgba(81, 91, 91, 0.14);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
}

/* 验证页英文小标题 */
.access-small-title {
    margin: 0 0 15px;
    color: var(--color-gold);
    font-family: Arial, sans-serif;
    font-size: 10px;
    letter-spacing: 4px;
}

/* 验证页主标题 */
.access-card h2 {
    margin: 0 0 22px;
    color: var(--color-text);
    font-family:
        "Cormorant Garamond",
        "Noto Serif SC",
        serif;
    font-size: 42px;
    font-weight: 500;
}

/* 验证问题 */
.access-question {
    margin: 0 0 22px;
    color: var(--color-text-muted);
    font-size: 17px;
}

/* 答案输入框 */
.access-input {
    width: 100%;
    margin-bottom: 16px;
    padding: 14px 18px;
    color: var(--color-text);
    background: rgba(255, 255, 255, 0.75);
    border: 1px solid var(--color-border);
    border-radius: 25px;
    outline: none;
    font-family: "Noto Sans SC", sans-serif;
    font-size: 16px;
    text-align: center;
}

/* 点击输入框时 */
.access-input:focus {
    border-color: var(--color-qiyu);
    box-shadow:
        0 0 0 3px rgba(145, 170, 179, 0.15);
}

/* 验证按钮 */
#verifyButton {
    width: 100%;
    background: var(--color-qiyu-hover);
}

/* 错误信息 */
.access-message {
    min-height: 24px;
    margin: 14px 0 0;
    color: #b66f6f;
    font-size: 14px;
}

/* 验证成功后隐藏验证页面 */
body.site-unlocked .access-gate {
    display: none;
}