/* ======== 全局自定义配色方案（深蓝与亮橙） ======== */
:root {
    --primary-dark: #101c3a;
    --primary: #174ea6;
    --accent: #ffb400; /* 亮橙 */
    --accent-hover: #ff9600;
    --bg-grey: #f5f6fa;
    --card-bg: #171f35;
    --text-dark: #101c3a;
    --text-light: #fff;
    --shadow: 0 4px 32px rgba(16, 28, 58, 0.15);
    --card-radius: 18px;
}

/* 全局样式重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.7;
    color: var(--primary-dark);
    background: var(--bg-grey);
    overflow-x: hidden;
    letter-spacing: 0.01em;
}

/* ======== 导航栏 ======== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(16, 28, 58, 0.97);
    box-shadow: var(--shadow);
    z-index: 1000;
    transition: background 0.3s, box-shadow 0.3s;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1.15rem 2.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--accent);
    letter-spacing: 2px;
    text-shadow: 0 1px 10px rgba(255,180,0,0.08);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2.2rem;
}

.nav-link {
    text-decoration: none;
    color: var(--text-light);
    font-weight: 500;
    padding: 0.3em 0.8em;
    border-radius: 7px;
    font-size: 1.09rem;
    transition: color 0.2s, background 0.2s;
    position: relative;
    letter-spacing: 0.02em;
}

.nav-link:hover, .nav-link:focus {
    color: var(--primary-dark);
    background: var(--accent);
    outline: none;
}

.nav-link::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -5px;
    width: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), var(--primary));
    border-radius: 2px;
    transition: width 0.28s cubic-bezier(0.6,0,0.4,1);
}

.nav-link:hover::after, .nav-link:focus::after {
    width: 100%;
}

/* ======== Section通用样式 ======== */
.section {
    min-height: 100vh;
    padding: 110px 0 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: transparent;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2.2rem;
    width: 100%;
}

.section-title {
    font-size: 2.75rem;
    text-align: center;
    margin-bottom: 3.2rem;
    color: var(--primary-dark);
    position: relative;
    padding-bottom: 1.2rem;
    letter-spacing: 0.04em;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 94px;
    height: 4px;
    background: linear-gradient(90deg, var(--accent), var(--primary));
    border-radius: 5px;
    box-shadow: 0 0 10px #ffb40044;
}

/* ======== Banner区域 ======== */
.banner {
    background: linear-gradient(120deg, #192550 35%, #284174 87%);
    color: var(--text-light);
    text-align: center;
    padding-top: 140px;
    box-shadow: 0 6px 28px rgba(16,28,58,0.07);
    border-radius: 0 0 32px 32px;
}

.banner-content {
    max-width: 850px;
    margin: 0 auto;
    padding: 2.5rem 2rem 2rem;
    border-radius: var(--card-radius);
}

.banner-title {
    font-size: 3.6rem;
    margin-bottom: 1.15rem;
    font-weight: 800;
    text-shadow: 0 2px 24px rgba(17,23,49,0.19);
    animation: fadeInUp 1s cubic-bezier(0.5,0,0.8,1);
}

.banner-subtitle {
    font-size: 1.55rem;
    margin-bottom: 2.1rem;
    opacity: 0.92;
    animation: fadeInUp 1s 0.19s backwards;
}

.btn-primary {
    display: inline-block;
    padding: 14px 38px;
    background: linear-gradient(90deg, var(--accent), var(--accent-hover));
    color: var(--primary-dark);
    text-decoration: none;
    border-radius: 999px;
    font-weight: 700;
    font-size: 1.07rem;
    border: none;
    box-shadow: 0 2px 14px #ffb40026;
    transition: transform 0.25s, box-shadow 0.23s, background 0.23s;
    animation: fadeInUp 1s 0.35s backwards;
    letter-spacing: 0.07em;
    cursor: pointer;
}

.btn-primary:hover, .btn-primary:focus {
    transform: translateY(-3px) scale(1.036);
    background: var(--accent-hover);
    box-shadow: 0 10px 32px #ffb4003b;
    color: #fff;
}

/* ======== 关于我区域 ======== */
.about {
    background: var(--bg-grey);
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3.5rem;
    align-items: stretch;
    padding: 2.6rem 0 1.6rem;
}

.about-text p {
    margin-bottom: 1.2rem;
    font-size: 1.14rem;
    line-height: 1.95;
    color: #374264;
    background: #fff;
    padding: 1.34rem 1.8rem;
    border-radius: var(--card-radius);
    box-shadow: 0 2px 18px rgba(23,31,53,0.045);
}

.about-image {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 280px;
}

.placeholder-image {
    width: 280px;
    height: 280px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--accent) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-size: 1.27rem;
    box-shadow: 0 10px 36px #171f3540;
    font-weight: 600;
    letter-spacing: 0.04em;
}

/* ======== 技能区域 ======== */
.skills {
    background: #fff;
}

.skills-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 2.1rem;
    padding-bottom: 0.3rem;
}

.skill-card {
    background: var(--card-bg);
    color: #fff;
    padding: 2.2rem 1.5rem;
    border-radius: var(--card-radius);
    text-align: center;
    box-shadow: 0 6px 24px rgba(16,28,58,0.13);
    transition: transform 0.23s, box-shadow 0.23s, border 0.3s;
    border: 1.6px solid transparent;
    position: relative;
    overflow: hidden;
}

.skill-card:hover, .skill-card:focus-within {
    transform: translateY(-8px) scale(1.04);
    box-shadow: 0 14px 28px #ffb40019;
    border-color: var(--accent);
    z-index: 2;
}

.skill-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.25rem;
    background:linear-gradient(135deg, var(--primary), var(--accent));
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-size: 2rem;
    font-weight: bold;
    box-shadow: 0 2px 12px #ffb40026;
}

.skill-name, .skill-card h3 {
    margin-bottom: 0.8rem;
    color: var(--accent);
    font-size: 1.17rem;
    font-weight: 600;
    letter-spacing: 0.03em;
}

.skill-card p {
    color: #e1e9fc;
    line-height: 1.7;
    font-size: 1.04rem;
}

/* ======== 作品集区域 ======== */
.portfolio {
    background: var(--bg-grey);
}

.portfolio-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 2.3rem;
    padding-bottom: 0.7rem;
}

.portfolio-item {
    background: #fff;
    border-radius: var(--card-radius);
    overflow: hidden;
    box-shadow: 0 8px 32px #141f3413;
    transition: transform 0.25s, box-shadow 0.2s;
    display: flex;
    flex-direction: column;
    min-width: 0;
}

.portfolio-item:hover, .portfolio-item:focus-within {
    transform: translateY(-10px) scale(1.0115);
    box-shadow: 0 18px 45px #ffb40021;
}

.portfolio-image {
    width: 100%;
    height: 200px;
    overflow: hidden;
    background: linear-gradient(120deg, var(--primary) 0%, var(--accent) 100%);
    display: flex;
    align-items: center;
    justify-content: center;
}

.portfolio-image .placeholder-image {
    width: 100%;
    height: 100%;
    border-radius: 0;
    background: linear-gradient(135deg, var(--primary), var(--accent));
}

.portfolio-info {
    padding: 2rem 1.6rem 1.4rem 1.6rem;
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.portfolio-info h3 {
    margin-bottom: 0.7rem;
    color: var(--primary-dark);
    font-size: 1.3rem;
    font-weight: 700;
    letter-spacing: 0.035em;
}

.portfolio-info p {
    margin-bottom: 1.3rem;
    color: #384079;
    line-height: 1.7;
    font-size: 1.07rem;
}

.btn-secondary {
    display: inline-block;
    padding: 10px 28px;
    background: linear-gradient(90deg, var(--primary), var(--accent));
    color: #fff;
    text-decoration: none;
    border-radius: 30px;
    font-weight: 600;
    font-size: 1.07rem;
    transition: background 0.27s, box-shadow 0.2s;
    box-shadow: 0 2px 10px #171f3522;
    letter-spacing: 0.04em;
    border: none;
    cursor: pointer;
}

.btn-secondary:hover, .btn-secondary:focus {
    background: linear-gradient(90deg, var(--accent), var(--accent-hover));
    box-shadow: 0 6px 18px #ffb40033;
    outline: none;
}

/* ======== 联系我区域 ======== */
.contact {
    background: #fff;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3.5rem;
    padding: 2.2rem 0 1.2rem;
}

.contact-info h3 {
    margin-bottom: 1.65rem;
    color: var(--primary-dark);
    font-size: 1.15rem;
    font-weight: 700;
}

.contact-info p {
    margin-bottom: 1.1rem;
    font-size: 1.11rem;
    color: #283056;
}

.contact-form {
    background: var(--bg-grey);
    padding: 2.2rem 1.7rem 1.6rem;
    border-radius: var(--card-radius);
    box-shadow: 0 2px 20px #101c3a12;
}

.form-group {
    margin-bottom: 1.6rem;
}

.form-group input,
.form-group textarea {
    width: 100%;
    padding: 14px 16px;
    border: 2px solid #e5e7f0;
    border-radius: 7px;
    font-family: inherit;
    font-size: 1.04rem;
    background: #fff;
    color: #222e4a;
    transition: border-color 0.23s, box-shadow 0.23s;
    box-shadow: 0 1px 5px #b5bfd526;
}

.form-group input:focus,
.form-group textarea:focus {
    outline: 2px solid var(--accent);
    border-color: var(--accent-hover);
    box-shadow: 0 2px 16px #ffb40022;
}

.form-group textarea {
    resize: vertical;
    min-height: 120px;
}

/* ======== 页脚 ======== */
.footer {
    background: var(--primary-dark);
    color: #fff;
    text-align: center;
    padding: 2.4rem 0;
    font-size: 1rem;
    letter-spacing: 0.02em;
    border-radius: 22px 22px 0 0;
    margin-top: 38px;
    box-shadow: 0 -4px 24px #101c3a14;
}

/* ======== 动画 ======== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(34px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* ======== 响应式设计 ======== */
@media (max-width: 950px) {
    .nav-container,
    .container {
        padding: 0 1rem;
    }
    .about-content,
    .contact-content {
        gap: 2.2rem;
    }
    .skills-grid,
    .portfolio-grid {
        gap: 1.3rem;
    }
}

@media (max-width: 768px) {
    .nav-menu {
        gap: 1.0rem;
    }

    .nav-link {
        font-size: 1rem;
        padding: 0.3em 0.7em;
    }

    .banner-title {
        font-size: 2.35rem;
    }

    .banner-subtitle {
        font-size: 1.1rem;
    }

    .section-title {
        font-size: 1.7rem;
    }

    .about-content,
    .contact-content {
        grid-template-columns: 1fr;
        padding: 1.7rem 0 1.2rem;
    }

    .skills-grid,
    .portfolio-grid {
        grid-template-columns: 1fr;
    }

    .placeholder-image {
        width: 170px;
        height: 170px;
    }
    .banner-content {
        padding: 0.6rem 0.2rem;
    }
}

@media (max-width: 480px) {
    .nav-container, .container {
        padding: 0 0.25rem;
    }

    .nav-menu {
        gap: 0.45rem;
    }

    .nav-link {
        font-size: 0.88rem;
        padding: 0.2em 0.4em;
        border-radius: 4px;
    }

    .banner-title {
        font-size: 1.34rem;
    }

    .section-title {
        font-size: 1.05rem;
    }

    .section {
        padding: 85px 0 20px;
    }

    .about-content,
    .contact-content {
        gap: 1rem;
        padding: 0.7rem 0 0.3rem;
    }

    .portfolio-info {
        padding: 1.1rem 0.7rem 1rem 0.7rem;
    }
}