/* assets/css/style.css */

@font-face {
    font-family: 'LongCang';
    src: url('../fonts/LongCang-Regular.woff2') format('woff2');
    font-weight: 400;
    font-display: swap;
}

:root {
    --pink-base: #ffe4ec;
    --pink-soft: #ffd6e8;
    --pink-strong: #ff9fba;
    --pink-deep: #f48fb1;
    --milk-white: #fff9f5;
    --gold: #f6c453;
    --text-primary: #5c3d4f;
    --text-secondary: #7a5367;
    --shadow-soft: 0 25px 45px rgba(92, 61, 79, 0.18);
    --font-heading: 'LongCang', 'Ma Shan Zheng', 'Zhi Mang Xing', 'STKaiti', 'KaiTi', 'Songti SC', serif;
    --font-body: 'Songti SC', 'Noto Serif SC', 'Source Han Serif SC', 'STSong', 'SimSun', serif;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    min-height: 100vh;
    font-family: var(--font-body);
    background: radial-gradient(circle at top left, rgba(255, 255, 255, 0.8), transparent 45%),
                radial-gradient(circle at 20% 80%, rgba(255, 193, 218, 0.6), transparent 40%),
                linear-gradient(135deg, #fff0f5, #ffd9e8 60%, #ffeef5);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 32px 20px 48px;
    overflow-x: hidden;
    position: relative;
}

body::after {
    content: '';
    position: fixed;
    inset: 0;
    background: url('data:image/svg+xml,%3Csvg width="160" height="160" viewBox="0 0 160 160" xmlns="http://www.w3.org/2000/svg"%3E%3Cg fill="%23ffe4ec" fill-opacity="0.3"%3E%3Cpath d="M55 64c3-12 21-12 24 0 3-12 21-12 24 0 3 12-9 22-24 34-15-12-27-22-24-34Z"/%3E%3C/g%3E%3C/svg%3E') repeat;
    opacity: 0.4;
    z-index: 0;
    pointer-events: none;
}

.page-wrapper {
    width: 100%;
    max-width: 840px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 32px;
    z-index: 2;
}

#particles {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 1;
    overflow: hidden;
}

/* Envelope */
.envelope-stage {
    cursor: pointer;
    position: relative;
    z-index: 5;
    transition: opacity 0.8s ease, transform 0.8s ease;
    perspective: 1200px;
}

.envelope-stage.opened {
    opacity: 0;
    transform: translateY(-20px) scale(0.92);
    pointer-events: none;
}

.envelope-stage:focus-visible {
    outline: 2px solid var(--gold);
    outline-offset: 8px;
}

.envelope {
    width: 320px;
    height: 210px;
    background: linear-gradient(145deg, #ffd6e8, #ffc7da);
    border-radius: 18px;
    position: relative;
    box-shadow: var(--shadow-soft);
    overflow: hidden;
}

.envelope::after {
    content: '';
    position: absolute;
    inset: 12px;
    border-radius: 16px;
    border: 2px dashed rgba(246, 196, 83, 0.45);
}

.envelope-flap {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(255, 255, 255, 0.95), rgba(255, 214, 232, 0.95));
    clip-path: polygon(0 0, 100% 0, 50% 60%);
    transform-origin: top;
    transition: transform 1s ease;
    z-index: 2;
    transform-style: preserve-3d;
    backface-visibility: hidden;
}

.envelope-stage.opened .envelope-flap {
    transform: rotateX(180deg);
}

.letter-preview {
    position: absolute;
    bottom: 36px;
    width: 100%;
    text-align: center;
    font-size: 1.2rem;
    letter-spacing: 1px;
    font-family: var(--font-heading);
    color: #b14d6d;
    z-index: 3;
}

.heart-seal {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    padding: 10px 22px;
    border-radius: 999px;
    background: var(--milk-white);
    color: var(--pink-strong);
    font-weight: 600;
    font-size: 0.95rem;
    box-shadow: 0 8px 20px rgba(244, 143, 177, 0.35);
    z-index: 4;
    animation: pulse 1.8s infinite ease-in-out;
}

@keyframes pulse {
    0% { transform: translate(-50%, -50%) scale(1); }
    50% { transform: translate(-50%, -50%) scale(1.08); }
    100% { transform: translate(-50%, -50%) scale(1); }
}

/* Letter */
.letter-shell {
    width: min(92vw, 720px);
    max-height: 85vh;
    background: rgba(255, 253, 249, 0.9);
    border-radius: 28px;
    padding: 24px;
    box-shadow: var(--shadow-soft);
    border: 1px solid rgba(255, 214, 232, 0.8);
    backdrop-filter: blur(8px);
    position: relative;
    z-index: 5;
    opacity: 0;
    transform: translateY(18px) scale(0.96);
    transition: opacity 0.9s ease, transform 0.9s ease;
    overflow-y: auto;
}

.letter-shell.revealed {
    opacity: 1;
    transform: translateY(0) scale(1);
}

.letter-content {
    position: relative;
    padding: 8px 8px 48px;
}

.letter-header {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 16px;
    margin-bottom: 24px;
}

.letter-header h2 {
    font-size: 2.1rem;
    font-family: var(--font-heading);
    color: var(--pink-deep);
    letter-spacing: 1px;
}

.relationship-counter {
    min-width: 180px;
    background: linear-gradient(135deg, rgba(255, 214, 232, 0.9), rgba(255, 255, 255, 0.9));
    border-radius: 18px;
    padding: 12px 20px;
    border: 1px solid rgba(246, 196, 83, 0.3);
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.6);
    text-align: center;
}

.counter-label {
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.counter-value {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--pink-deep);
    margin-top: 4px;
}

#text-area {
    font-size: 1.08rem;
    line-height: 1.9;
    color: var(--text-secondary);
    white-space: pre-wrap;
    min-height: 180px;
    margin-bottom: 8px;
    font-family: var(--font-body);
}

.cursor {
    animation: blink 1s infinite;
    color: var(--pink-strong);
}

@keyframes blink {
    0%, 40% { opacity: 1; }
    50%, 100% { opacity: 0; }
}

.message-panel {
    margin-top: 28px;
    padding: 18px 20px;
    border-radius: 20px;
    background: rgba(255, 214, 232, 0.4);
    border: 1px dashed rgba(244, 143, 177, 0.6);
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.heart-button {
    align-self: flex-start;
    background: linear-gradient(135deg, var(--pink-strong), #ffb0c9);
    border: none;
    color: #fff;
    padding: 10px 20px;
    border-radius: 999px;
    font-size: 0.95rem;
    font-weight: 600;
    cursor: pointer;
    box-shadow: 0 10px 18px rgba(255, 143, 178, 0.35);
    transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.heart-button:focus-visible {
    outline: 2px solid #fff;
    outline-offset: 3px;
}

.heart-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 14px 22px rgba(255, 143, 178, 0.45);
}

.message-display {
    min-height: 22px;
    font-size: 1rem;
    color: var(--text-primary);
    opacity: 0;
    transform: translateY(6px);
    transition: opacity 0.35s ease, transform 0.35s ease;
}

.message-display.show {
    opacity: 1;
    transform: translateY(0);
}

.timeline {
    margin-top: 32px;
}

.timeline h3 {
    font-size: 1.3rem;
    color: var(--pink-deep);
    margin-bottom: 16px;
    font-family: var(--font-heading);
}

.timeline-list {
    position: relative;
    padding-left: 24px;
}

.timeline-list::before {
    content: '';
    position: absolute;
    left: 8px;
    top: 4px;
    bottom: 4px;
    width: 2px;
    background: linear-gradient(180deg, rgba(246, 196, 83, 0.4), rgba(244, 143, 177, 0.6));
}

.timeline-item {
    position: relative;
    margin-bottom: 20px;
    padding-left: 16px;
}

.timeline-item:last-child {
    margin-bottom: 0;
}

.timeline-icon {
    position: absolute;
    left: -5px;
    top: 0;
    width: 16px;
    height: 16px;
    background: #fff;
    border: 2px solid var(--pink-strong);
    border-radius: 50%;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    font-size: 0.7rem;
    color: var(--pink-strong);
}

.timeline-title {
    font-weight: 600;
    color: var(--text-primary);
}

.timeline-time {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 2px;
}

.timeline-desc {
    color: var(--text-secondary);
    line-height: 1.6;
}

.signature-area {
    margin-top: 32px;
    text-align: right;
    font-weight: 600;
    color: var(--text-primary);
}

#signature {
    font-family: var(--font-heading);
    font-size: 1.2rem;
    letter-spacing: 1px;
    color: var(--pink-deep);
}

.secret-easter-egg {
    position: fixed;
    bottom: 20px;
    right: 20px;
    z-index: 25;
}

.secret-heart {
    pointer-events: auto;
    background: rgba(255, 255, 255, 0.6);
    border: 1px solid rgba(244, 143, 177, 0.6);
    border-radius: 999px;
    font-size: 1rem;
    color: var(--pink-deep);
    cursor: pointer;
    opacity: 0.65;
    transition: opacity 0.3s ease, transform 0.3s ease, background 0.3s ease;
    padding: 6px 14px;
    box-shadow: 0 6px 18px rgba(244, 143, 177, 0.25);
}

.secret-heart:hover,
.secret-heart:focus-visible {
    opacity: 1;
    transform: translateY(-2px);
    background: rgba(255, 255, 255, 0.95);
}

.secret-message {
    position: absolute;
    bottom: 48px;
    right: 0;
    margin: 0;
    padding: 16px 20px;
    border-radius: 18px;
    border: 1px dashed rgba(246, 196, 83, 0.6);
    background: rgba(255, 255, 255, 0.95);
    color: var(--text-secondary);
    line-height: 1.7;
    opacity: 0;
    transform: translateY(8px);
    transition: opacity 0.4s ease, transform 0.4s ease;
    pointer-events: none;
    max-width: min(320px, 80vw);
    width: max-content;
    box-shadow: var(--shadow-soft);
}

.secret-message.active {
    opacity: 1;
    transform: translateY(0);
    pointer-events: auto;
}

.secret-message-title {
    font-family: var(--font-heading);
    color: var(--pink-deep);
    margin-bottom: 6px;
}

/* Floating hearts */
.heart-particle {
    position: absolute;
    top: -10vh;
    color: rgba(255, 153, 186, 0.8);
    font-size: 20px;
    animation-name: floatDown;
    animation-timing-function: ease-in;
    animation-fill-mode: forwards;
    user-select: none;
    pointer-events: none;
}

@keyframes floatDown {
    0% {
        transform: translate3d(0, -10vh, 0) scale(var(--scale, 1));
        opacity: 0;
    }
    20% {
        opacity: var(--opacity, 0.8);
    }
    100% {
        transform: translate3d(var(--drift, 0), 110vh, 0) scale(calc(var(--scale, 1) * 0.8));
        opacity: 0;
    }
}

/* Responsive tweaks */
@media (max-width: 600px) {
    body {
        padding: 24px 16px 32px;
        align-items: flex-start;
    }

    .envelope {
        width: 280px;
        height: 190px;
    }

    .letter-shell {
        width: 100%;
        max-height: none;
        padding: 18px;
    }

    .letter-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .relationship-counter {
        width: 100%;
    }

    .message-panel,
    .timeline,
    .signature-area {
        margin-top: 24px;
    }

    .secret-easter-egg {
        bottom: 12px;
        right: 12px;
    }

    .secret-message {
        max-width: calc(100vw - 32px);
        bottom: 56px;
    }
}